Here is the backtrace:
This GDB was configured as "i386-marcel-freebsd"...(no debugging symbols found)... warning: core file may not match specified executable file. Core was generated by `dovecot-auth'. Program terminated with signal 6, Aborted. #0 0x181317af in ?? () (gdb) bt full #0 0x181317af in ?? () No symbol table info available. #1 0x18126856 in ?? () No symbol table info available. #2 0x0001303a in ?? () No symbol table info available. #3 0x00000006 in ?? () No symbol table info available. #4 0x00000000 in ?? () No symbol table info available. #5 0x00000000 in ?? () No symbol table info available. #6 0x00000286 in ?? () No symbol table info available. #7 0x181aaf4c in ?? () No symbol table info available. #8 0xbfbfea78 in ?? () No symbol table info available. #9 0x1819a0df in ?? () No symbol table info available. #10 0x00000006 in ?? () No symbol table info available. #11 0xbfbfea48 in ?? () No symbol table info available. #12 0x00000000 in ?? () No symbol table info available. #13 0x1819a0aa in ?? () No symbol table info available. #14 0x00000001 in ?? () No symbol table info available. #15 0x18094400 in ?? () No symbol table info available. #16 0xffffffdf in ?? () No symbol table info available. #17 0xffffffff in ?? () No symbol table info available. #18 0xffffffff in ?? () No symbol table info available. #19 0xffffffff in ?? () No symbol table info available. #20 0x18071a11 in ?? () No symbol table info available. #21 0x18094000 in ?? () No symbol table info available. #22 0x00000140 in ?? () No symbol table info available. #23 0x08079000 in mail_cache_register_fields () No symbol table info available. #24 0x08070000 in mbox_storage_sync_init () No symbol table info available. ---Type <return> to continue, or q <return> to quit--- #25 0x00000000 in ?? () No symbol table info available. #26 0x08478040 in ?? () No symbol table info available. #27 0x0848f100 in ?? () No symbol table info available. #28 0xbfbfea98 in ?? () No symbol table info available. #29 0x0805e684 in imap_thread () No symbol table info available. Previous frame inner to this frame (corrupt stack?) (gdb)